Analysis of information sources in references of the Wikipedia article "Irish Free State" in English language version.
it was legally clear that the treaty, and the associated provisional parliament and government, applied only to the 26 counties...[Article 11] implied politically – but not legally – that the Irish Free State had some right to Northern Ireland. But partition was acknowledged expressly in the treaty...following the text of article 12, [the address] requested that the powers of the parliament and government of the Irish Free State should no longer extend to Northern Ireland. This does not mean they had so extended on 6 December 1922.
It is certainly true that the Treaty went through the motions of including Northern Ireland within the Irish Free State while offering it the provision to opt out
The jurisdiction of the Free State was the island of Ireland. The Northern Ireland Parliament gave notice, as it was entitled to do, that it did not wish to come under the jurisdiction of the Free State. In Re Logue [1933] 67 ILTR 253 it was held that, because the notice took effect after the Constitution of the Irish Free State (Saorstát Eireann) had come into operation, most of those domiciled in Northern Ireland had become Irish citizens under Article 3 of the Constitution of the Irish Free State (Saorstát Éireann).
The jurisdiction of the Free State was the island of Ireland. The Northern Ireland Parliament gave notice, as it was entitled to do, that it did not wish to come under the jurisdiction of the Free State. In Re Logue [1933] 67 ILTR 253 it was held that, because the notice took effect after the Constitution of the Irish Free State (Saorstát Eireann) had come into operation, most of those domiciled in Northern Ireland had become Irish citizens under Article 3 of the Constitution of the Irish Free State (Saorstát Éireann).
It is certainly true that the Treaty went through the motions of including Northern Ireland within the Irish Free State while offering it the provision to opt out
it was legally clear that the treaty, and the associated provisional parliament and government, applied only to the 26 counties...[Article 11] implied politically – but not legally – that the Irish Free State had some right to Northern Ireland. But partition was acknowledged expressly in the treaty...following the text of article 12, [the address] requested that the powers of the parliament and government of the Irish Free State should no longer extend to Northern Ireland. This does not mean they had so extended on 6 December 1922.